I just want to let you know that it worked . A few things I'd like to mention:
1. I deleted all the existing dtb files in /boot, and copied over the -cubox ones from /boot/dtb (I probably should have symlinked, but I was afraid the bootloader couldn't follow it).
2. I had to remove the hostapd package just like the script does because of the conflict, like you mentioned
3. I didn't touch the boot scripts. /boot/uEnv.txt was very similar to what you linked me to, besides the consoleblank, vt.global_cursor_default, and loglevel settings.
captain got a reaction from Igor in 4 issues with the upgrade.armbian.com script on cubox-i